Alight-rail commuter train accelerates at a rate of 1.35 m/s. d a 33% part (a) how long does it take to reach its top speed of 85 km/h, in seconds, starting from rest? hints deduction per hint. hints remaining 1 feedback: deduction per feedback a 33 part (b) the same train ordinarily brakes at a rate of 1.8 m/s. how long does it take to come to a stop, in seconds, from its top speed? 433 part (c) in emergencies the train can slow more rapidly. coming to rest from 85 km/h in 7.9 5. what is the magnitude of the acceleration during emergency braking, in meters per square second?